As an disclosure relevant to a conventional electronic component, a multilayer chip inductor disclosed in, for example, Japanese Patent Laid-Open Publication No. 2001-358016, is known. FIG. 11 is an exploded oblique view of the multilayer chip inductor 500 disclosed in Japanese Patent Laid-Open Publication No. 2001-358016.
The multilayer chip inductor 500 includes a plurality of pieces of ferrite sheets 501, a plurality of coil conductors 502, and a plurality of through-hole conductors 503. The ferrite sheets 501 are rectangular sheets laminated to constitute a rectangular body of the multilayer chip inductor 500. The coil conductors 502 are provided on the ferrite sheets 501, and connected by the through-hole conductors 503 to constitute a helical coil.
Here, in the multilayer chip inductor 500, the coil conductors 502 are provided in pairs, each consisting of the coil conductors 502 that have the same shape and are connected in parallel. Therefore, the multilayer chip inductor 500 has a reduced direct-current resistance.
Incidentally, the multilayer chip inductor 500 disclosed in Japanese Patent Laid-Open Publication No. 2001-358016 might have defective connections at the through-hole conductors 503. Specifically, downstream ends of an upper pair of congruent coil conductors 502 are connected to upstream ends of a lower pair of congruent coil conductors 502 by a straight series of three through-hole conductors 503. The through-hole conductors 503 are formed by applying a conductor material to fill through-holes provided in the ferrite sheets 501. At this time, a very small amount of air is mixed into the conductors in the through-holes. That is, the conductors do not fill the through-holes densely. Therefore, in the case where multiple through-hole conductors 503 (in the case of the multilayer chip inductor 500, three through-hole conductors 503) are connected in a series, the through-hole conductors 503 are not sufficiently compressed upon pressure bonding of the ferrite sheets 501. As a result, gaps are created at the boundaries between the through-hole conductors 503 and the coil conductors 502. Consequently, defective connections might occur at the through-hole conductors 503.